sell out

British  

verb

1. Also (chiefly Brit): sell up.  to dispose of (supplies of something) completely by selling

2. informal (tr) to betray, esp through a secret agreement

3. informal (intr) to abandon one's principles, standards, etc

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noun

1. informal a performance for which all tickets are sold

2. a commercial success

3. informal a betrayal

4. informal a person who betrays their principles, standards, friends, etc

sell out Idioms  

1. Dispose of entirely by selling. For example, The rancher finally sold out to the oil company , or The tickets to the concert were sold out a month ago . [Late 1700s]

2. Betray one's cause or colleagues, as in He sold out to the other side . [ Slang ; late 1800s]

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Example Sentences

With every EFP round came fresh promises they would never sell out to "big beer".

From BBC • Mar. 6, 2026

Fans were encouraged to snap them up quickly before they sell out again.

From Los Angeles Times • Feb. 27, 2026

“We cannot just sell out of the AI companies,” said Nicolai Tangen, who runs Norway’s $2.1 trillion sovereign-wealth fund, when asked about its U.S. tech exposure in January.

From The Wall Street Journal • Feb. 13, 2026

The matches at Cardiff's 74,000 Principality Stadium usually sell out or reach high capacity for a tournament that has traditionally been a highlight of the Welsh sporting calendar.

From BBC • Feb. 12, 2026

Desperate as he was for a job, he was determined not to sell out, not to “start on that road,” as he put it.

From "Geeks: How Two Lost Boys Rode the Internet Out of Idaho" by Jon Katz